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The role of the sacrificial anode rod

The anode rod is the most important factor in determining the life of your water heater. An anode rod is a steel core wire surrounded with one of three different metals. These metals include aluminum, magnesium, and zinc. The rod is screwed into the top of your water heater and protects your water heater from rusting. When the tank is filled with water the anode rod sacrifices itself to protect the exposed steel of the water heater, through a method called electrolysis. Electrolysis happens when there are two pieces of metal connected inside of water, the process makes the anode rod corrode in place of the exposed steel in your water heater. During this process the more noble (less reactive) metal will corrode over the less (more reactive) noble metal. Aluminum, magnesium, and zinc are all much less noble than steel, meaning they will corrode before the steel, which is why they are used for anode rods.

Anode Rod Problems

The anode rod is designed to corrode in place of your water heater lining, when the rod has been completely corroded it no longer protects your water heater. A typical anode rod will last about 4-5 years but it depends on the amount of water traveling through your water heater. A water softener also shortens the life of your anode rods significantly. A depleted anode rod can and does cause your water heater problems. The first problem you can expect to encounter with a bad anode rod is the rusting of your water heater. If your water heater rusts you will most likely need to replace it, which will cost you much more than replacing an anode rod. Another problem you may encounter is having the anode rod break off and fall to the bottom of your water heater. The broken off rod will bounce around in the water heater anytime water passes through it, which will destroy the lining of the water heater very quickly. This creates cracks in the glass lining of the water heater which will drastically shorten your water heaters life. There is no question, failure to replace your anode rods in a timely fashion, will shorten your water heaters life.

Tanks with recurring odor problem:. Cleaning tank with 2 pints hydrogen peroxide also solves problem H2O2.
Change plumbing so hydrogen peroxide can be added easily.

Odor is caused by anodic metal reacting with bacteria. Power anode rod does not react with bacteria. Your tank might have 2 anode rods. Tanks with long warranties, and lifetime warranties have more than one anode rod. Read water heater manual. Replacing 1 anode with power anode rod leaves other anode rod inside tank that can react with bacteria and create odor.

You wrote: "A water softener also shortens the life of your anode rods significantly. "

Question for you...that confuses me because soft water means little or no mineral depoists (calcium etc.), right? So if mineral deposits are minimal, why does the anode degrade? Or is the degradation due to a different issue? Is it pH issue? Is the water from a water softener neutral 7.0 pH?

I am not smart enough to tell you the answer.

I hope you don't think that I am doubting you in any way. I'm just curious about it.

I had a similar thought the first time I read it. So far, I haven't any information.

Maybe it's something about the salts used must be corrosive to some of the metals in the anode. Could be if and when the water softener isn't maintained properly? or ...?

We have a2k members likely knowledgeable enough to tell us. Question now is, do they ever look at a thread like this one?

farmerman?

Probably. But I am pretty sure there are some others.

I cringe at the thought, ed, but waterboy might be your man on this one...

I'd rather eat dirt.

If I recall correctly:

Soft water is salty. Hard water has other minerals (such as calcium).

Soft water reduces the life of your sacrificial anode because it is more corrosive.

Extremely hard water is bad for your plumbing because the calcium precipitates out when the water is heated. The calcium narrows pipes, clogs faucets, reduces the efficiency of the water heater, etc.

Hard water also reacts with soap, causing salts to precipitate out ("soap scum").

Could be.

Thanks, drewdad.

This post is about A/Cs but it can go for any repair one does. Yesterday I was called in to work on an A/C that proved to be operating normally, inside, but the condenser, outside, would not start. I could tell it had recently ran, so I saw no reason to examine the thermostat, which I had installed the day before. My reasoning was that if I had done a bum job it would not have been operating normally to that point. The lead man had told me to install it and I did. We were switching from a manual one to digital. I examined every facet of that system before facing that the thermostat had to be the culprit. In short, by not first revisiting the last work done to the A/C I made extra work for myself, on what should have been my time off. One of the wires had not gotten tightened properly and so lost contact - a fact I discovered less than a minute after removing the cover. This is a lesson I have had to learn over and over, because I am at heart a gullible person.

I had dropped this thread because nobody seemed interested. Thanks for your comments.

An awesome thread to solve a lot problems of mine. I am very happy in finding this thread. Thanks for sharing this and offering me such problem solving page.